Internal improvement: Create shrinkwrap for truffle-cli

[CruzMolina]

Pins all packages/truffle deps & pushes shrinkwrap generated from all cli dependencies.

Inspired by #2555 .

[coveralls]

Coverage decreased (-0.02%) to 73.41% when pulling e727180 on shrinkwrapCLI into be5289a on develop.

[gnidan]

Don't we need this to automatically update?

[CruzMolina]

There's two cases that come to mind:

• If we add a dep to the cli, we'll need to update the shrinkwrap.
• If we expect or want devs to use the cli as a devDep, we'll need to update the shrinkwrap & publish the cli, after bumping/publishing the org pkgs.

It seems that we recommend devs/users install the cli globally and don't expect them to consume it as a devDep. Still, not sure whether we want to move forward with this.

[CruzMolina]

Closing since there doesn't seem to be interest in doing this.